Self adapting method of sampling frequency of audio frequency interface

Abstract

This invention provides one audio frequency interface sample rate self-adapting method, which comprises the following steps: a, according to audio frequency interface work rate and digital audio signal original sample to compute out audio interface output signal each point needed bit; b, audio frequency interface is to fill digital audio frequency signal of each sample point of output signal data value; then filling set data value to each sample point bit; c, outputting signal in step b and outputting each sample point effective information.

Description

technical field [0001] The invention relates to audio interface technology, in particular to an audio interface sampling rate adaptive method. Background technique [0002] Most of the current multimedia processors use digital audio processing technology, that is to say, the analog signal is converted into a digital signal and stored in the multimedia processor. When playing sound, the stored digital signal must first be restored to an analog signal, and then played. The decoder decoder (CODEC) in the multimedia processor completes the analog / digital conversion or digital / analog conversion of the signal. In the analog / digital conversion, the CODEC samples the analog signal according to a certain sampling rate to form a digital audio signal. The sampling rate is the original sampling rate of the converted digital audio signal, and the number of sampling bits of each sampling point of the digital audio signal is the same at the original sampling rate. The amount of data conta...

AI Technical Summary

Problems solved by technology

In this method, before playing the audio, first calculate the working frequency of the audio interface according to the original sampling rate of the played digital audio signal, and then set the calculated working frequency for the audio interface. Although this method makes the sampling rate of the audio interface The sampling rate is the same as the original sampling rate of the digital audio signal, which avoids the distortion of the digital audio signal played. However, the operation of changing the working frequency of the audio interface requires a powerful clock conversion circuit for the audio interface, which leads to complex hardware implementation and increased cost.

[0006] It can be seen that in the prior art, for the case where the sampling rate of the audio interface is inconsistent with the original sampling rate of the digital audio signal, the original sampling rate of the digital audio signal is converted to the sampling rate of the audio interface under the condition that the operating frequency of the audio interface remains unchanged. The method of high frequency will cause the signal to be distorted to a certain extent; in the case of variable working frequency of the audio interface, although the problem of signal distortion can be solved, the operation of changing the working frequency of the audio interface will lead to complex hardware implementation and cost rise

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